Although the present study did not focus on abnormalities in mineral metabolism as a causal mechanism for the progression of calcific aortic valve disease, previous clinical studies have demonstrated that a decrease in 1,25-dihydroxyvitamin D and an increase in parathyroid hormone (PTH) are the earliest mineral metabolic events that take place in CKD, while serum calcium and phosphate levels are altered later in the course of CKD [28]. The gene discussed is PTH; the disease is aortic valve calcification.